This invention relates to a method for preventing and treating asthma in mammals comprising administering a compound characterized as an inhibitor of a family of enzymes known as MEK kinases, which are groups of MAP (mitogen-associated protein kinase) and Erk (extracellular signal-regulated) Kinases. These are enzymes that regulate phosphorylation of substrates in mammals.
Asthma is a heterogeneous disorder of the airways that afflicts millions of people. Airway inflammation, hyperresponsiveness, and obstruction characterize the condition. The disease often causes spasms of the bronchial smooth muscle system, and affects both the upper and lower respiratory tracts. There are several forms of asthma, characterized by varying degrees of severity. Mild asthma, for example, is defined as brief episodes of wheezing, with or without dyspnea or cough. Moderately severe asthma is defined as wheezing and dyspnea, and can be with or without cough and expectoration, but generally interferes with daily activities and/or sleeping. Severe asthma is characterized by incapacitation due to dyspnea, and the afflicted patient typically is unable to eat or sleep normally, is very anxious, and is often exhausted. A condition known as status asthmaticus is the most severe form of asthma, and generally requires intensive hospital care, and may even prove fatal. The disease may occur as a result of both allergic and nonallergic mechanisms.
While there are several treatments available for relieving the symptoms and discomfort associated with asthma, there are no cures. Moreover, the current treatments often cause side effects that exacerbate the discomfort and precipitate other debilitating conditions. Mild asthma generally is treated with beta-adrenergic drugs, as well as antihistamines, especially in the case of children, to prevent or abort sporadic episodes. Moderately severe and severe asthma are generally treated with adrenergic agents and bronchodilators, as well as corticosteroids. Other actions caused by antiasthmatic agents which limit their widespread use include headache, fatigue, dry mouth, nervousness, and in some cases addiction and substance abuse. Recent advances in the understanding of the pathogenesis and treatment of asthma is discussed more fully by Grayson et al., The Mount Sinai Journal of Medicine, September 1998;65(4):246-256.
Because asthma is so prevalent in both children and adults, there is an ongoing need for agents that can treat the disease, or at least relieve the symptoms that accompany the disease, without causing undesirable side effects. We have now discovered that MEK inhibitors are particularly useful for treating asthma and relieving the symptoms that accompany the disease. An object of this invention is therefore to provide a new method for preventing and treating asthmatic conditions.
This invention provides a method of preventing and treating asthma, said method comprising the step of administering to a patient an antiasthmatic-effective amount of a MEK inhibitor. Selective MEK inhibitors are those compounds which inhibit the MEK 1 and MEK 2 enzymes without substantial inhibition of other such enzymes. In a preferred embodiment, the invention provides a method for preventing or treating asthma by administering a MEK inhibitor. In a further embodiment, the invention provides a method for preventing and/or treating asthma comprising administering an effective amount of the selective MEK inhibitor described in U.S. Pat. No. 5,525,625, incorporated herein by reference, which selective MEK inhibitor is 2-(2-amino-3-methoxyphenyl)-4-oxo-4H-[1]benzopyran.
In another preferred embodiment, the MEK inhibitor to be administered is a phenyl amine derivative of Formula I: 
In Formula (I), R1 is hydrogen, hydroxy, C1-C8 alkyl, C1-C8 alkoxy, halo, trifluoromethyl, or CN. R2 is hydrogen. R3, R4, and R5 are independently selected from hydrogen, hydroxy, halo, trifluoromethyl, C1-C8 alkyl, C1-C8 alkoxy, nitro, CN, and xe2x80x94(O or NH)mxe2x80x94(CH2)nxe2x80x94R9. R9 is hydrogen, hydroxy, COOH, or NR10R11; n is 0-4; m is 0 or 1. Each of R10 and R11 is independently selected from hydrogen and C1-C8 alkyl, or taken together with the nitrogen to which they are attached can complete a 3-10 member cyclic ring optionally containing 1, 2, or 3 additional heteroatoms selected from O, S, NH, or Nxe2x80x94(C1-C8 alkyl). Z is COOR7, tetrazolyl, CONR6R7, CONHNR10R11, or CH2OR7. R6 and R7 independently are hydrogen, C1-C8 alkyl C2-C8 alkenyl, C2-C8 alkynyl, (CO)xe2x80x94C1-C8 alkyl, aryl, heteroaryl, C3-C10 cycloalkyl, or C3-C10 (cycloalkyl optionally containing one, two, or three heteroatoms selected from O, S, NH, or N alkyl); or R6 and R7 together with the nitrogen to which they are attached complete a 3-10 member cyclic ring optionally containing 1, 2, or 3 additional heteroatoms selected from O, S, NH, or N alkyl. In formula (I), any of the foregoing alkyl, alkenyl, aryl, heteroaryl, heterocyclic, and alkynyl groups can be unsubstituted or substituted by halo, hydroxy, C1-C6 alkoxy, amino, nitro, C1-C4 alkylamino, di(C1-C4)alkylamino, C3-C6 cycloalkyl, phenyl, phenoxy, C3-C5 heteroaryl or heterocyclic radical, or C3-C5 heteroaryloxy or heterocyclic radicaloxy. The invention also provides a pharmaceutically acceptable salt, ester, amide, or prodrug of each of the disclosed MEK inhibitors.
Preferred embodiments of Formula (I) have a structure wherein: (a) R1 is hydrogen, methyl, methoxy, fluoro, chloro, or bromo; (b) R2 is hydrogen; (c) R3, R4, and R5 independently are hydrogen, fluoro, chloro, bromo, iodo, methyl, methoxy, or nitro; (d) R10 and R11 independently are hydrogen or methyl; (e) Z is COOR7, tetrazolyl, CONR6R7, CONHNR10R11, or CH2OR7; R6 and R7 independently are hydrogen, C1-4 alkyl, heteroaryl, or C3-5 cycloalkyl optionally containing one or two heteroatoms selected from O, S, or NH; or R6 and R7 together with the nitrogen to which they are attached complete a 5-6 member cyclic ring optionally containing 1 or 2 additional heteroatoms selected from O, NH or N-alkyl; and wherein any of the foregoing alkyl or aryl groups can be unsubstituted or substituted by halo, hydroxy, methoxy, ethoxy, or heteroaryloxy (such as 2,3,4,5,6-pentafluorophenyl); (f) Z is COOR7; (g) R7 is H, pentafluorophenyl, or tetrazolyl; (h) R3, R4, and R5 are independently H, fluoro, or chloro; (i) R4 is fluoro; (j) two of R3, R4, and R5 are fluoro; or (k) or combinations of the above. In another preferred embodiment of Formula (I), R1 is methyl, fluoro, chloro, or bromo.
In a more preferred embodiment, the MEK inhibitor is selected from a compound in Formula (I) Compound Table below.
In another preferred embodiment, the MEK inhibitor is a compound of Formula II 
In Formula (II), R1a is hydrogen, hydroxy, C1-C8 alkyl, C1-C8 alkoxy, halo, trifluoromethyl, or CN. R2a is hydrogen. Each of R3a, R4a, and R5a is independently selected from hydrogen, hydroxy, halo, trifluoromethyl, C1-C8 alkyl, C1-C8 alkoxy, nitro, CN, and (O or NH)mxe2x80x94(CH2)nxe2x80x94R9a. R9a is hydrogen, hydroxy, CO2H or NR10aR11a; n is 0-4; and m is 0 or 1. Each of R10a and R11a is independently hydrogen or C1-C8 alkyl, or taken together with the nitrogen to which they are attached can complete a 3- to 10-member cyclic ring optionally containing one, two, or three additional heteroatoms selected from O, S, NH, or Nxe2x80x94(C1-C8 alkyl). R6a is hydrogen, C1-C8 alkyl, (CO)xe2x80x94(C1-C8 alkyl), aryl, aralkyl, or C3-C10 cycloalkyl. R7a is hydrogen, C1-C8 alkyl, C2-C8 alkenyl, C2-C8 alkynyl, C3-C10 (cycloalkyl or cycloalkyl optionally containing a heteroatom selected from O, S, or NR9a). In Formula (II), any of the foregoing any of the foregoing alkyl, alkenyl, aryl, heteroaryl, heterocyclic, and alkynyl groups can be unsubstituted or substituted by halo, hydroxy, C1-C6 alkoxy, amino, nitro, C1-C4 alkylamino, di(C1-C4)alkylamino, C3-C6 cycloalkyl, phenyl, phenoxy, C3-C5 heteroaryl or heterocyclic radical, or C3-C5 heteroaryloxy or heterocyclic radical-oxy; or R6a and R7a taken together with the N to which they are attached can complete a 5- to 10-membered cyclic ring, optionally containing one, two, or three additional heteroatoms selected from O, S, or NR10aR11a. The invention also encompasses pharmaceutically acceptable salts, esters, amides or prodrugs of each of the disclosed compounds.
Preferred embodiments of Formula (II) are those structures wherein: (a) R1a is H, methyl, fluoro, or chloro; (b) R2a is H; R3a, R4a, and R5a are each H, Cl, nitro, or F; (c) R6a is H; (d) R7a is methyl, ethyl, 2-propenyl, propyl, butyl, pentyl, hexyl, cyclopropylmethyl, cyclobutyl methyl, cyclopropylmethyl, or cyclopropylethyl; (e) the 4xe2x80x2 position is I, rather than Br; (f) R4a is F at the 4 position, para to the COxe2x80x94Nxe2x80x94R6axe2x80x94OR7a group and meta to the bridging nitrogen; (f) R3a or R5a is F; (g) at least one of R3a, R4a, and R5a is F; (h) R1a is methyl or chloro; or (i) or a combination of the above.
In a more preferred embodiment the MEK inhibitor is a compound selected from Formula (II) Compound Table below.
In the most preferred embodiment of this invention, a compound selected from the following is administered to a patient (ie, a mammal) in an amount that is effective to prevent or treat rheumatoid arthritis or osteoarthritis:
2-(2-Chloro4-iodophenylamino)-N-cyclopropylmethoxy-3,4-difluorobenzamide (PD184352); 2-(2-Methyl-4-iodophenylamino)-N-hydroxy-4-fluorobenzamide(PD170611); 2-(2-Methyl-4-iodophenylamino)-N-hydroxy-3,4-difluoro-5-bromobenzamide(PD171984); 2-(2-Methyl-4-iodophenylamino)-N-cyclopropylmethoxy-3,4-difluoro-5-bromobenzamide (PD177168); 2-(2-Methyl-4-iodophenylamino)-N-cyclobutylmethoxy-3,4-difluoro-5-bromobenzamide(PD 180841); 2-(2-Chloro-4-iodophenylamino)-N-cyclopropylmethoxy-3,4-difluoro-5-bromobenzamide(PD 184161); 2-(2-Chloro-4-iodophenylamino)-N-hydroxy-3,4-difluoro-5-bromobenzamide (PD184386); 2-(2-Chloro4-iodophenylamino)-N-cyclobutylmethoxy-3,4-difluorobenzamide(PD185625); 2-(2-Chloro-4-iodophenylamino)-N-hydroxy-4-fluorobenzamide(PD 185848); 2-(2-Methyl-4-iodophenylamino)-N-hydroxy-3,4-difluorobenzamide (PD 188563); 2-(2-Methyl-4-iodophenylamino)-N-cyclopropylmethoxy-3,4,5-trifluorobenzamide (PD 198306); and 2-(2-Chloro-4-iodophenylamino)-N-cyclopropylmethoxy-4-fluorobenzamide (PD 203311); and the benzoic acid derivatives thereof. For example, the benzoic acid derivative of PD 198306 is 2-(2-Methyl-4-iodophenylamino)-3,4,5-trifluorobenzoic acid.
Additional preferred compounds include 2-(2-chloro4-iodophenylamino)-5-chloro-N-cyclopropylmethoxy-3,4-difluorobenzamide (PD 297189), 2-(4-iodophenylamino)-N-cyclopropylmethoxy-5-chloro-3,4-difluorobenzamide (PD 297190), 2-(4-iodophenylamino)-5-chloro-3,4-difluorobenzoic acid (PD 296771), 2-(2-chloro4-iodophenylamino)-5-chloro-3,4-difluorobenzoic acid (PD 296770), 5-chloro-3,4-difluoro-2-(4-iodo-2-methylphenylamino)-benzoic acid (PD 296767); and 5-chloro-N-cyclopropylmethoxy-3,4-difluoro-2-(4-iodo-2-methylphenylamino)-benzamide (PD 298127).
The invention further provides methods of synthesis and synthetic intermediates.
Other features and advantages of the invention are apparent from the detailed description, examples, and claims set forth.
In a further preferred embodiment of this invention, a mitotic inhibitor is administered to a patient suffering from cancer and in need of treatment in combination with a selective MEK inhibitor selected from: 2-(2-Chloro-4-iodophenylamino)-N-cyclopropylmethoxy-3,4-difluorobenzamide (PD184352); 2-(2-Methyl-4-iodophenylamino)-N-hydroxy-4-fluorobenzamide (PD 170611); 2-(2-Methyl-4-iodophenylamino)-N-hydroxy-3,4-difluoro-5-bromobenzamide (PD 171984), a more preferred compound; 2-(2-Methyl-4-iodophenylamino)-N-cyclopropylmethoxy-3,4-difluoro-5-bromobenzamide (PD 177168); 2-(2-Methyl-4-iodophenylamino)-N-cyclobutylmethoxy-3,4-difluoro-5-bromobenzamide (PD 180841); 2-(2-Chloro4-iodophenylamino)-N-cyclopropylmethoxy-3,4-difluoro-5-bromobenzamide (PD 184161); 2-(2-Chloro-4-iodophenylamino)-N-hydroxy-3,4-difluoro-5-bromobenzamide (PD 184386); 2-(2-Chloro-4-iodophenylamino)-N-cyclobutylmethoxy-3,4-difluorobenzamide (PD 185625); 2-(2-Chloro4-iodophenylamino)-N-hydroxy4-fluorobenzamide (PD 185848); 2-(2-Methyl4-iodophenylamino)-N-hydroxy-3,4-difluorobenzamide (PD 188563); 2-(2-Methyl4-iodophenylamino)-N-cyclopropylmethoxy-3,4,5-trifluorobenzamide (PD 198306); and 2-(2-Chloro-4-iodophenylamino)-N-cyclopropylmethoxy-4-fluorobenzamide (PD 203311); and the benzoic acid derivatives thereof. For example, the benzoic acid derivative of PD 198306 is 2-(2-Methyl-4-iodophenylamino)-3,4,5-trifluorobenzoic acid.
This invention provides a method of preventing or treating asthma in a patient which comprises administering to a patient suffering from asthma and in need of treatment, or to a patient at risk for developing an asthmatic attack, an anti-asthmatic effective amount of a MEK inhibitor. The invention provides a method of preventing and treating all forms of asthma and relieving the symptoms that accompany the disease. The invention is preferably practiced by administering a phenyl amine MEK inhibitor of Formula I or Formula II. Such MEK phenyl amine compounds are specific MEK 1 and MEK 2 inhibitors, meaning that they inhibit these enzymes without inhibiting other enzymes to a great extent.
The compounds of the present invention, which can be used to treat septic shock, are MEK inhibitors. A MEK inhibitor is a compound that shows MEK inhibition when tested in the assays titled xe2x80x9cEnzyme Assaysxe2x80x9d in U.S. Pat. No. 5,525,625, column 6, beginning at line 35. The complete disclosure of U.S. Pat. No. 5,525,625 is hereby incorporated by reference. An example of a MEK inhibitor is 2-(2-amino-3-methoxyphenyl)-4-oxo-4H-[1]benzopyran. Specifically, a compound is a MEK inhibitor if a compound shows activity in the assay titled xe2x80x9cCascade Assay for Inhibitors of the MAP Kinase Pathway,xe2x80x9d column 6, line 36 to column 7, line 4 of the U.S. Pat. No. 5,525,625 and/or shows activity in the assay titled xe2x80x9cIn Vitro MEK Assayxe2x80x9d at column 7, lines 4 to 27 of the above-referenced patent.
Some of the terms used herein are defined below and by their usage throughout this disclosure.
The term xe2x80x9cpatientxe2x80x9d means all animals including humans. Examples of patients include humans, cows, dogs, cats, goats, sheep, horses, and pigs. The mammals to be treated according to this invention are patients who have developed asthma and are suffering from the symptoms associated with disease, or who are at risk for developing the disease, for example having a family history of asthma. Those skilled in the medical art are readily able to identify individual patients, particularly children, who are afflicted with asthma, as well as those who are susceptible to developing the disease.
As used herein, the term xe2x80x9carylxe2x80x9d means a cyclic, bicyclic, or tricyclic aromatic ring moiety having from five to twelve carbon atoms. Examples of typical aryl groups include phenyl, naphthyl, and fluorenyl. The aryl may be substituted by one, two, or three groups selected from fluoro, chloro, bromo, iodo, alkyl, hydroxy, alkoxy, nitro, amino, alkylamino, or dialkylamino. Typical substituted aryl groups include 3-fluorophenyl, 3,5-dimethoxyphenyl, 4-nitronaphthyl, 2-methyl-4-chloro-7-aminofluorenyl, and the like.
The term xe2x80x9caryloxyxe2x80x9d means an aryl group bonded through an oxygen atom, for example phenoxy, 3-bromophenoxy, naphthyloxy, and 4-methyl-1-fluorenyloxy.
xe2x80x9cHeteroarylxe2x80x9d means a cyclic, bicyclic, or tricyclic aromatic ring moiety having from four to eleven carbon atoms and one, two, or three heteroatoms selected from O, S, or N. Examples include furyl, thienyl, pyrrolyl, pyrazolyl, imidazolyl, triazolyl, thiazolyl, oxazolyl, xanthenyl, pyronyl, indolyl, pyrimidyl, naphthyridyl, pyridyl, benzinnidazolyl, and triazinyl. The heteroaryl groups can be unsubstituted or substituted by one, two, or three groups selected from fluoro, chloro, bromo, iodo, alkyl, hydroxy, alkoxy, nitro, amino, alkylamino, or dialkylamino. Examples of substituted heteroaryl groups include chloropyranyl, methylthienyl, fluoropyridyl, amino-1,4-benzisoxazinyl, nitroisoquinolinyl, and hydroxyindolyl.
The heteroaryl groups can be bonded through oxygen to make heteroaryloxy groups, for example thienyloxy, isothiazolyloxy, benzofuranyloxy, pyridyloxy, and 4-methylisoquinolinyloxy.
The term xe2x80x9calkylxe2x80x9d means straight and branched chain aliphatic groups. Typical alkyl groups include methyl, ethyl, isopropyl, tert.-butyl, 2,3-dimethylhexyl, and 11-dimethylpentyl. The alkyl groups can be unsubstituted or substituted by halo, hydroxy, alkoxy, amino, alkylamino, dialkylamino, cycloalkyl, aryl, aryloxy, heteroaryl, or heteroaryloxy, as those terms are defined herein. Typical substituted alkyl groups include chloromethyl, 3-hydroxypropyl, 2-dimethylaminobutyl, and 2-(hydroxymethylamino)ethyl. Examples of aryl and aryloxy substituted alkyl groups include phenylmethyl, 2-phenylethyl, 3-chlorophenylmethyl, 1,1-dimethyl-3-(2-nitrophenoxy)butyl, and 3,4,5-trifluoronaphthylmethyl. Examples of alkyl groups substituted by a heteroaryl or heteroaryloxy group include thienylmethyl, 2-furylethyl, 6-furyloxyoctyl, 4-methylquinolyloxymethyl, and 6-isothiazolylhexyl. Cycloalkyl substituted alkyl groups include cyclopropylmethyl, 2-cyclohexyethyl, piperidyl-2-methyl, 2-(piperidin-1-yl)-ethyl, 3-(morpholin-4-yl)propyl.
xe2x80x9cAlkenylxe2x80x9d means a straight or branched carbon chain having one or more double bonds. Examples include but-2-enyl, 2-methyl-prop-2-enyl, 1,1-dimethyl-hex-4-enyl, 3-ethyl-4-methyl-pent-2-enyl, and 3-isopropyl-pent-4-enyl. The alkenyl groups can be substituted with halo, hydroxy, alkoxy, amino, alkylamino, dialkylamino, aryl, aryloxy, heteroaryl, or heteroyloxy, for example 2-bromoethenyl, 3-hydroxy-2-butenyl, 1-aminoethenyl, 3-phenylprop-2-enyl, 6-thienyl-hex-2-enyl, 2-furyloxy-but-2-enyl, and 4-naphthyloxy-hex-2-enyl. xe2x80x9cAlkynylxe2x80x9d means a straight or branched carbon chain having at least one triple bond. Typical alkynyl groups include prop-2-ynyl, 2-methyl-hex-5-ynyl, 3,4-dimethyl-hex-5-ynyl, and 2-ethyl-but-3-ynyl. The alkynyl groups can be substituted as the alkyl and alkenyl groups, for example, by aryl, aryloxy, heteroaryl, or heteroaryloxy, for example 4-(2-fluorophenyl)-but-3-ynyl, 3-methyl-5-thienylpent-4-ynyl, 3-phenoxy-hex-4-ynyl, and 2-furyloxy-3-methyl-hex-4-ynyl.
The alkenyl and alkynyl groups can have one or more double bonds or triple bonds, respectively, or a combination of double and triple bonds. For example, typical groups having both double and triple bonds include hex-2-en-4-ynyl, 3-methyl-5-phenylpent-2-en-4-ynyl, and 3-thienyloxy-hex-3-en-5-ynyl.
The term xe2x80x9ccycloalkylxe2x80x9d means a nonaromatic ring or fused rings. Examples include cyclopropyl, cyclobutyl, cyclopenyl, cyclooctyl, bicycloheptyl, adamantyl, and cyclohexyl. The ring can optionally contain one, two, or three heteroatoms selected from O, S, or N. Such groups include tetrahydrofuryl, tetrahydropyrrolyl, octahydrobenzofuranyl, morpholinyl, piperazinyl, pyrrolidinyl, piperidinyl, octahydroindolyl, and octahydrobenzothiofuranyl. The cycloalkyl groups can be substituted with the same substituents as an alkyl and alkenyl groups, for example, halo, hydroxy, aryl, and heteroaryloxy. Examples include 3-hydroxycyclohexyl, 2-aminocyclopropyl, 2-phenylpyrrolidinyl, and 3-thienylmorpholine-1-yl.
Selective MEK 1 or MEK 2 inhibitors are those compounds which inhibit the MEK 1 or MEK 2 enzymes, respectively, without substantially inhibiting other enzymes such as MKK3, PKC, Cdk2A, phosphorylase kinase, EGF, and PDGF receptor kinases, and C-src. In general, a selective MEK 1 or MEK 2 inhibitor has an IC50 for MEK 1 or MEK 2 that is at least one-fiftieth ({fraction (1/50)}) that of its IC50 for one of the above-named other enzymes. Preferably, a selective inhibitor has an IC50 that is at least {fraction (1/100)}, more preferably 1/500, and even more preferably {fraction (1/1000)}, {fraction (1/5000)}, or less than that of its IC50 or one or more of the above-named enzymes.
The MEK inhibitors of the present method can be administered to a patient as part of a pharmaceutically acceptable composition. The compositions can be administered to humans and animals either orally, rectally, parenterally (intravenously, intramuscularly,or subcutaneously), intracistemally, intravaginally, intraperitoneally, intravesically, locally (powders, ointments, or drops), or as a buccal or nasal spray.
Compositions suitable for parenteral injection may comprise physiologically acceptable sterile aqueous or nonaqueous solutions, dispersions, suspensions or emulsions, and sterile powders for reconstitution into sterile injectable solutions or dispersions. Examples of suitable aqueous and nonaqueous carriers, diluents, solvents, or vehicles include water, ethanol, polyols (propyleneglycol, polyethyleneglycol, glycerol, and the like), suitable mixtures thereof, vegetable oils (such as olive oil), and injectable organic esters such as ethyl oleate. Proper fluidity can be maintained, for example, by the use of a coating such as lecithin, by the maintenance of the required particle size in the case of dispersions and by the use of surfactants.
These compositions may also contain adjuvants such as preserving, wetting, emulsifying, and dispensing agents. Prevention of the action of microorganisms can be ensured by various antibacterial and antifungal agents, for example, parabens, chlorobutanol, phenol, sorbic acid, and the like. It may also be desirable to include isotonic agents, for example sugars, sodium chloride, and the like. Prolonged absorption of the injectable pharmaceutical form can be brought about by the use of agents delaying absorption, for example, aluminum monostearate and gelatin.
Solid dosage forms for oral administration include capsules, tablets, pills, powders, and granules. In such solid dosage forms, the active compound is admixed with at least one inert customary excipient (or carrier) such as sodium citrate or dicalcium phosphate or (a) fillers or extenders, as for example, starches, lactose, sucrose, glucose, mannitol, and silicic acid, (b) binders, as for example, carboxymethylcellulose, alignates, gelatin, polyvinylpyrrolidone, sucrose, and acacia, (c) humectants, as for example, glycerol, (d) disintegrating agents, as for example, agarxe2x80x94agar, calcium carbonate, potato or tapioca starch, alginic acid, certain complex silicates, and sodium carbonate, (e) solution retarders, as for example paraffin, (f) absorption accelerators, as for example, quaternary ammonium compounds, (g) wetting agents, as for example, cetyl alcohol and glycerol monostearate, (h) adsorbents, as for example, kaolin and bentonite, and (i) lubricants, as for example, talc, calcium stearate, magnesium stearate, solid polyethylene glycols, sodium lauryl sulfate, or mixtures thereof. In the case of capsules, tablets, and pills, the dosage forms may also comprise buffering agents.
Solid compositions of a similar type may also be employed as fillers in soft and hard-filled gelatin capsules using such excipients as lactose or milk sugar as well as high molecular weight polyethyleneglycols, and the like.
Solid dosage forms such as tablets, dragees, capsules, pills, and granules can be prepared with coatings and shells, such as enteric coatings and others well-known in the art. They may contain opacifying agents, and can also be of such composition that they release the active compound or compounds in a certain part of the intestinal tract in a delayed manner. Examples of embedding compositions which can be used are polymeric substances and waxes. The active compounds can also be in micro-encapsulated form, if appropriate, with one or more of the above-mentioned excipients.
Liquid dosage forms for oral administration include pharmaceutically acceptable emulsions, solutions, suspensions, syrups, and elixirs. In addition to the active compounds, the liquid dosage forms may contain inert diluents commonly used in the art, such as water or other solvents, solubilizing agents and emulsifiers, as for example, ethyl alcohol, isopropyl alcohol, ethyl carbonate, ethyl acetate, benzyl alcohol, benzyl benzoate, propyleneglycol, 1,3-butyleneglycol, dimethylformamide, oils, in particular, cottonseed oil, groundnut oil, corn germ oil, olive oil, castor oil and sesame oil, glycerol, tetrahydrofurfuryl alcohol, polyethyleneglycols, and fatty acid esters of sorbitan or mixtures of these substances, and the like.
Besides such inert diluents, the composition can also include adjuvants, such as wetting agents, emulsifying and suspending agents, sweetening, flavoring, and perfuming agents.
Suspensions, in addition to the active compounds, may contain suspending agents, as for example, ethoxylated isostearyl alcohols, polyoxyethylene sorbitol and sorbitan esters, microcrystalline cellulose, aluminum metahydroxide, bentonite, agar-agar and tragacanth, or mixtures of these substances, and the like.
Compositions for rectal administrations are preferably suppositories which can be prepared by mixing the compounds of the present invention with suitable non-irritating excipients or carriers such as cocoa butter, polyethyleneglycol, or a suppository wax, which are solid at ordinary temperatures but liquid at body temperature and therefore, melt in the rectum or vaginal cavity and release the active component.
Dosage forms for topical administration of a compound of this invention include ointments, powders, sprays, and inhalants. The active component is admixed under sterile conditions with a physiologically acceptable carrier and any preservatives, buffers, or propellants as may be required. Ophthalamic formulations, eye ointments, powders, and solutions are also contemplated as being within the scope of this invention.
The compounds of the present method can be administered to a patient at dosage levels in the range of about 0.1 to about 1000 mg per day. For a normal human adult having a body weight of about 70 kg, a dosage in the range of about 0.01 to about 100 mg per kg of body weight per day is preferable. The specific dosage used, however, can vary. For example, the dosage can depend on a numbers of factors including the requirements of the patient, the severity of the condition being treated, and the pharmacological activity of the compound being used. The determination of optimum dosages for a particular patient is well-known to those skilled in the art.
The compounds of the present method can be administered as pharmaceutically acceptable salts, esters, amides, or prodrugs. The term xe2x80x9cpharmaceutically acceptable salts, esters, amides, and prodrugsxe2x80x9d as used herein refers to those carboxylate salts, amino acid addition salts, esters, amides, and prodrugs of the compounds of the present invention which are, within the scope of sound medical judgment, suitable for contact with the tissues of patients without undue toxicity, irritation, allergic response, and the like, commensurate with a reasonable benefit/risk ratio, and effective for their intended use, as well as the zwitterionic forms, where possible, of the compounds of the invention.
The term xe2x80x9csaltsxe2x80x9d refers to the relatively non-toxic, inorganic and organic acid addition salts of compounds of the present invention. These salts can be prepared in situ during the final isolation and purification of the compounds or by separately reacting the purified compound in its free base form with a suitable organic or inorganic acid and isolating the salt thus formed. Representative salts include the hydrobromide, hydrochloride, sulfate, bisulfate, nitrate, acetate, oxalate, valerate, oleate, palmitate, stearate, laurate, borate, benzoate, lactate, phosphate, tosylate, citrate, maleate, fumarate, succinate, tartrate, naphthylate, mesylate, glucoheptonate, lactiobionate and laurylsulphonate salts, and the like. These may include cations based on the alkali and alkaline earth metals, such as sodium, lithium, potassium, calcium, magnesium and the like, as well as nontoxic ammonium, quaternary ammonium, and amine cations including, but not limited to ammonium, tetramethylammonium, tetraethylammonium, methylamine, dimethylamine, trimethylamine, triethylamine, ethylamine, and the like. (See, for example, S. M. Berge, et al., xe2x80x9cPharmaceutical Salts,xe2x80x9d J. Pharm. Sci., 1977;66:1-19 which is incorporated herein by reference.)
Examples of pharmaceutically acceptable, non-toxic esters of the compounds of this invention include C1-C6 alkyl esters wherein the alkyl group is a straight or branched chain. Acceptable esters also include C5-C7 cycloalkyl esters as well as arylalkyl esters such as, but not limited to benzyl. C1-C4 alkyl esters are preferred. Esters of the compounds of the present invention may be prepared according to conventional methods.
Examples of pharmaceutically acceptable, non-toxic amides of the compounds of this invention include amides derived from ammonia, primary C1-C6 alkyl amines and secondary C1-C6 dialkyl amines wherein the alkyl groups are straight or branched chain. In the case of secondary amines the amine may also be in the form of a 5 or 6 membered heterocycle containing one nitrogen atom. Amides derived from ammonia, C1-C3 alkyl primary amines and C1-C2 dialkyl secondary amines are preferred. Amides of the compounds of the invention may be prepared according to conventional methods.
The term xe2x80x9cprodrugxe2x80x9d refers to compounds that are rapidly transformed in vivo to yield the parent compound of the above formula, for example, by hydrolysis in blood. A thorough discussion is provided in T. Higuchi and V. Stella, xe2x80x9cPro-drugs as Novel Delivery Systems,xe2x80x9d Vol. 14 of the A.C.S. Symposium Series, and in Bioreversible Carriers in Druz Design, ed. Edward B. Roche, American Pharmaceutical Association and Pergamon Press, 1987, both of which are incorporated herein by reference.
In addition, the compounds of the present method can exist in unsolvated as well as solvated forms with pharmaceutically acceptable solvents such as water, ethanol, and the like. In general, the solvated forms are considered equivalent to the unsolvated forms for the purposes of the present invention.
Some of the compounds of the present method can exist in different stereoisometric forms by virtue of the presence of chiral centers. It is contemplated that all stereoisometric forms of the compounds as well as mixtures thereof, including racemic mixtures, form part of this invention.
The examples presented below are intended to illustrate particular embodiments of the invention and are not intended to limit the scope of the specification, including the claims, in any way. After the priority date of the present disclosure, related syntheses and MEK inhibition data were also published in WO 99/01421 and WO 99/01426, hereby incorporated by reference.
The 2-(4-bromo and 4-iodo phenylamino)-benzoic acid derivatives of Formula I can be prepared from commercially available starting materials utilizing synthetic methodologies well-known to those skilled in organic chemistry. A typical synthesis is carried out by reacting a 4-bromo or 4-iodo aniline with a benzoic acid having a leaving group at the 2-position to give a 2-(phenylamino)-benzoic acid. This process is depicted in Scheme 1. 
where L is a leaving group, for example halo such as fluoro.
The reaction of aniline and the benzoic acid derivative generally is accomplished by mixing the benzoic acid with an equimolar quantity or excess of the aniline in an unreactive organic solvent such as tetrahydrofuran or toluene, in the presence of a base such as lithium diisopropylamide, n-butyl lithium, sodium hydride, triethylamine, and Hunig""s base. The reaction generally is carried out at a temperature of about xe2x88x9278xc2x0 C. to about 100xc2x0 C., and normally is complete within about 2 hours to about 4 days. The product can be isolated by removing the solvent, for example by evaporation under reduced pressure, and further purified, if desired, by standard methods such as chromatography, crystallization, or distillation.
The 2-(phenylamino)-benzoic acid (e.g., Formula I, where R7 is hydrogen) can be reacted with an organic or inorganic base such as pyridine, triethylamine, calcium carbonate, or sodium hydroxide to produce a pharmaceutically acceptable salt. The free acids can also be reacted with an alcohol of the formula HOR7 (where R7 is other than hydrogen, for example methyl) to produce the corresponding ester. Reaction of the benzoic acid with an alcohol can be carried out in the presence of a coupling agent. Typical coupling reagents include 2-ethoxy-1-ethoxycarbonyl-1,2-dihydroquinoline (EEDQ), 1,3-dicyclohexylcarbodiimide (DCC), bromo-tris(pyrrolidino)- phosphonium hexafluorophosphate (PyBrOP), and (benzotriazolyloxy) tripyrrolidino phosphonium hexafluorophosphate (PyBOP). The phenylamino benzoic acid and alcohol derivative normally are mixed in approximately equimolar quantities in an unreactive organic solvent such as dichloromethane, tetrahydrofuran, chloroform, or xylene, and an equimolar quantity of the coupling reagent is added. A base such as triethylamine or diisopropylethylamine can be added to act as an acid scavenger if desired. The coupling reaction generally is complete after about 10 minutes to 2 hours, and the product is readily isolated by removing the reaction solvent, for instance by evaporation under reduced pressure, and purifying the product by standard methods such as chromatography or crystallizations from solvents such as acetone, diethyl ether, or ethanol.
The benzamides of the invention, Formula I where Z is CONR6R7, are readily prepared by reacting the foregoing benzoic acids with an amine of the formula HNR6R7. The reaction is carried out by reacting approximately equimolar quantities of the benzoic acid and amine in an unreactive organic solvent in the presence of a coupling reagent. Typical solvents are chloroform, dichloromethane, tetrahydrofuran, benzene, toluene, and xylene. Typical coupling reagents include DCC, EEDQ, PyBrOP, and PyBOP. The reaction is generally complete after about 10 minutes to about 2 hours when carried out at a temperature of about 0xc2x0 C. to about 60xc2x0 C. The product amide is readily isolated by removing the reaction solvent, for instance by evaporation, and further purification can be accomplished by normal methods such as chromatography, crystallization, or distillation. The hydrazides (z=CONHNR10R11) are similarly prepared by coupling a benzoic acid with a hydrazine of the formula H2HNR10R11.
The benzyl alcohols of the invention, compounds of Formula I where Z is CH2OR6 and R6 is hydrogen, are readily prepared by reduction of the corresponding benzoic acid according to the following Scheme 2. 
Typical reducing agents commonly employed include borane in tetrahydrofuran. The reduction normally is carried out in an unreactive organic solvent such as tetrahydrofuran, and generally is complete within about 2 hours to about 24 hours when conducted at a temperature of about 0xc2x0 C. to about 40xc2x0 C.